It has been known to subject a transparent acrylic plate for example to the printing by an inkjet printer for example to operate the pixel density to prepare a light guide plate for uniform reflection. Another technique has been conventionally known to change a printing density for example by a distance from a peripheral section including a light source (e.g., LED) (see Patent Publication 1 for example).
In a screen printing, there is a disadvantage of available resolution, thus resulting in a known phenomenon of a visible dot pattern according to which a dot pattern is undesirably visible. In order to avoid this, it has been also suggested to use a light diffusion sheet for example and to provide a minute pitch for the elimination of the visible dot pattern (see Patent Publication 2 for example).